Entry guide for strip mill

ABSTRACT

A mechanism for feeding strip material into the nip between a pair of strip mill rollers includes opposed guides for engaging and capturing the edges of the material being fed into the nip. Each guide has a side wall, a top plate and a bottom plate that together define a tapered channel. The wide end or throat of the channel initially receives the material, while the small end of the channel guides the material into the adjacent nip. The guides are movable toward and away from each other to accommodate strip materials of different widths. Each guide journals a series of vertically extending rollers of decreasing lengths upon which the associated side edge of the strip material sequentially rides as it moves toward the nip. The lengths of the rollers substantially exceed the expected thicknesses of the strip material so that the lower ends of the rollers wear at a faster rate then their upper ends. When the wear on the lower ends of the rollers has progressed to a predetermined degree, the rollers can be easily inverted to permit continued operation of the mechanism.

BACKGROUND OF THE INVENTION

The present invention relates in general to web or strip materialhandling mechanisms, and more particularly to an entry guide for feedingstrip material into the nip or bite area between a pair of mill rollers.

Strip mill entry guides are known in the art, as evidenced by U.S. Pat.2,402,546 and 3,740,989. The function of entry guides is to control andproperly position strip material as it is fed between an opposed pair ofmill rolls or rollers wherein the strip is worked. For example, severalstands or sets of mill rollers are used together to sequentially reducerelatively thick slab steel into relatively thin strip steel that iswidely used as sheet metal in automotive, appliance, and otherapplications. When the slab steel is rolled at high temperature, theprocess is known as "hot milling", while the process of rolling lowertemperature slab steel is known as "cold milling". While the presentinvention is pertinent to "cold milling" and other strip handlingprocesses, its primary advantages are found in "hot milling"applications.

The "hot milling" of slab steel through a series of stands of millrollers is a complex process requiring that the sets of rollers operateat different speeds, roller pressures and the like due to the gradualthinning and lengthening of the high temperature steel strip beingrolled. Each stand of mill rollers requires an entry guide mechanism toeffectively transfer the strip material to it from an adjacent set ofrollers. The entry guide mechanism must serve two primary functions, inamely feeding or threading the leading edge of the strip into the nipof the associated mill rollers, and then maintaining the strip ofmaterial in proper position as its length continues through the nip ofthe associated rollers. Ideally, the entry guide mechanism for eachstand should be generally identical to permit interchangeability andfacilitate maintenance. By being generally identical to each other, eachentry guide mechanism must be able to accommodate strip materialtraveling at different speeds and having different thicknesses and thusmasses. Also, the entry guide mechanism must be of a design andconstruction that is rugged and user accommodating so as to provide forreliable operation under adverse conditions common in a "hot milling"environment.

SUMMARY OF THE INVENTION

In accordance with the present invention, a frame structure is providedthat is movable toward and away from an associated stand of millrollers. A pair of opposed horizontally extending guides providing avertically tapering channel are mounted on the frame and engage andcapture the side edges of the strip material as it moves between theguides toward the nip of the associated mill rollers.

A series of vertical axis guide rollers extend along the horizontallength of each guide, each roller having an upper portion and a lowerportion. The side edges of the strip material engage and ride primarilyon the lower portions of the rollers since the vertical lengths of therollers are substantially greater than the expected thickness of thestrip material, whereby the lower roller portions will wear faster thantheir upper portions. When wear of the lower roller portions hasproceeded to a predetermined degree, the rollers can be easily invertedwherein primarily the former upper roller portions now bear against andguide the strip material.

Preferably, spray means such as nozzles apply cooling liquid to thelower portions of the rollers to lengthen their service life. Also, theguide rollers farthest from the nip of the mill rollers are of adiameter larger than those closest to the nip so as to better absorbhigher impact forces caused by the leading edge of the strip as it firstengages the large diameter rollers during an initial threadingoperation. Also, the guides are preferably movable toward and away fromeach other to accommodate strip material of varying widths.

Thus, the strip mill entry guide in accordance with the invention hasproven to be highly rugged, adaptable and reliable without attendanthigh cost and complexity.

BRIEF DESCRIPTION OF THE DRAWINGS

A fuller understanding of the invention may be had by referring to thefollowing description and claims taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 schematically illustrates the application of the presentinvention to a strip milling operation;

FIG. 2 is an elevation view in cross section of a strip mill entry guidein accordance with the invention;

FIG. 3 is a plan view in cross section of the strip mill entry guide;

FIG. 4 is a front end view in cross section of the strip mill entryguide;

FIG. 5 is an elevation view in partial cross section of a right sideguide element of the strip mill entry guide;

FIG. 6 is an elevation view in cross section of a roller member used inthe guide element of FIG. 5; and

FIG. 7 is an exploded view of the roller element of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1, a strip rolling mill 10 is schematicallyillustrated in a simplified manner to demonstrate the application of thepresent invention wherein a relatively thick strip or slab 20 of hightemperature steel is fed into the mill 10, where it is worked andgradually reduced primarily in thickness to provide sheet metal. Suchmilling operation in general being well known in the art. As illustratedin FIG. 1, the mill 10 includes four rolling mill stands 12, 14, 16 13and 18, each having a pair of working rolls 12a-12b, 14a-14b, 16a-16band 18a-18b. The rotational axes of the roller pairs are opposed to eachother and on respective sides of the strip material 20 wherein thematerial, as it is fed between the nip or bite area between the rollers,can be worked and pressed by the rollers to, in effect, be extrudedprimarily in a lengthwise dimension, thereby reducing the thickness ofthe material in a progressive and gradual manner, as illustrated. As isknown in the art, to initiate the operation of the rolling mill 10 onthe sheet material 20, the leading edge of the material is fed in thedirection indicated sequentially, first through mill stand 18, then 16,then 14, and finally mill stand 12. This process can continue until thedesired thickness of the material has been obtained by appropriatecontrol of the mill roll pairs.

With further reference to FIG. 1, a rolling mill entry guide 30 inaccordance with the present invention is provided for each rolling millstand 12, 14, 16 and 18. Each rolling mill entry guide 30 feeds theassociated strip material 20 into the nip between its associated pair ofstrip mill rollers by engaging and capturing the edges of the materialbeing fed into the nip of the associated rollers. It is to be noted thatthe primary function of each guide 30 is to capture and in effect threadthe incoming leading edge of the strip material and then feed it intothe nip area of its associated mill rollers. Once the threadingoperation of the material 20 has been completed as illustrated in FIG.1, the guides 30 assist in maintaining proper position and alignment ofthe material as it moves through the strip rolling mill 10.

As shown in FIG. 1, each rolling mill entry guide 30 includes aconventional knockdown roll mechanism 40 to guide the leading edge ofthe web material 20 into a throat area of the guide 30 in a manner to besubsequently illustrated. As is well recognized in the art, as theleading edge of the material 20 exits an associated pair of rollers, itdoes not necessarily travel in a linear direction along the path shownin FIG. 1, but rather can move up and down, vertically and side to sideas a result of it being extruded from the nip area of the rollers it hasjust exited. It is the function of the guide mechanism 30 to capture andguide the material into the next set of rollers and the knockdown rollmechanism 40 assists in the guiding operation.

In a manner to be subsequently illustrated, each rolling mill entryguide 30 can move toward and away from its associated pair of millrollers so as to allow access to both the entry guide 30 and the niparea of the mill rollers for maintenance purposes and the like. It isimportant that movement of the guides 30 toward their associated rollerpairs be limited and such limiting of movement is provided by manuallyadjustable stop members 50 which engage and abut the frames 12c, 14c,16c and 18c of the rolling mill stands. The detailed operation andstructure of the manually adjustable stop members will be subsequentlyillustrated. Thus it can be seen, that the strip rolling mill 10 withits rolling mill stands 12, 14, 16 and 18 and its associated rollingmill entry guides 30, cooperate to primarily reduce the thickness, andthus increase the length, of the metal slab or strip material. It shouldbe noted that the material 20 is worked at high temperature in the orderof 2000° F. to lessen the mechanical force required to work it. However,the high temperature of the strip material being worked necessitatesthat the entry guide 30 be designed so as to be able to tolerate suchhigh temperatures and the caustic environment resulting therefrom.

Turning to FIG. 2 of the drawings, a more detailed illustration of arolling mill entry guide is shown by an elevation view in cross section.For purposes of simplification, the rolling mill entry guide 30associated with rolling mill stand 12 of FIG. 1 has been illustrated, itbeing recognized that the other rolling mill stands 14, 16 and 18 areequipped with the same rolling mill entry guide 30 illustrated in FIG.2.

The rolling mill entry guide 30 in accordance with the present inventionincludes a frame 32 which is supported at its lower end by the floor 19of the rolling mill in a manner to be more fully illustrated. An upperend 32a of the frame 32 supports at its right end, as illustrated, theearlier noted knockdown roll mechanism 40 which includes a knockdownroll 42 engageable with an incoming leading edge of the strip material20. The knockdown roll 42 is supported at one end of an arm member 44having its other end fixedly mounted to the upper end of the frame 32aby a member 46. The upper end 32a of the frame 30 also supports at itsleft end, a roll wiper mechanism 60 of conventional design whichincludes a roll wiper support arm 62 which at its distal end supports awiper blade 64 engageable with the outer cylindrical surface of theupper mill roller 12a so as to wipe it clean during a rolling operation.At the lower end of the frame 32, a lower frame cross member 32b hasattached to it one end of a hydraulic actuator 34. The end of thehydraulic actuator 34 attached to the cross member 32b is a pistonportion 38 that reciprocates into and out of an associated cylinderportion 36 which includes a base element 36a fixed to the floor 19 ofthe mill, as illustrated. Upon operation of the actuator 34, the rollingmill entry guide 30 can move back and forth, as illustrated by arrow 39so as to move the entry guide 30 either away from or toward the pair ofmill rollers 9 12a, 12b. As noted earlier with regard to FIG. 1, theextent of movement of the entry guide 30 toward the mill rollers 12b islimited by engagement of the stop mechanisms 50 (see FIGS. 1, 3) withthe associated frame of the rolling mill, which will be more fullydescribed hereafter.

With continued reference to FIG. 2 and with reference also to FIG. 3,which is a plan view in cross section of the entry guide 30, a betterunderstanding of the structure and operation of the entry guide can behad.

As referenced to the direction of feed indicated in FIGS. 2 and 3, apair of opposed, horizontally extending guides 70, 80 are mounted on theframe 32 for engaging and capturing the vertical side edges of the stripmaterial 20. The guides 70, 80 define a horizontally extending channelthat vertically tapers as said material moves through the channel towardthe nip area 12d between the mill rollers 12a, 12b. The guide 70captures and directs the right edge 20a of the material 20 while theguide 80 captures and directs the left 20b edge of the material 20toward the associated mill rollers. The right edge guide 70 includes atop plate 72, a vertically, downwardly extending side wall 74 and bottomplate 76. In a similar manner, the left edge guide 80 includes a topplate 82 (See FIG. 4), a side wall 84 and a bottom plate 86.

As shown most clearly in FIG. 2, the top plate 72 and bottom plate 76vertically taper away from each other as they extend away from the nip12d, the bottom plate 76 being generally horizontal while the top plate72 extends generally upwardly as its length progresses from the nip 12d.Likewise, the top plate 82 and the bottom plate 86 vertically taper awayfrom each other as they extend away from the nip 12d. The side wall 74includes along its length a series of vertical axis rollers 100, 110,120 that extend along the horizontal length of the guide 70. In asimilar manner, the guide 80 includes a corresponding set of rollers100a, 110a and 120a that are generally identical in dimension andstructure to the rollers 100, 110, 120 forming a part of the right edgeguide 70. As best shown in FIG. 2, the vertical lengths of the rollersare substantially greater than the expected thickness of the material 20wherein during 3) of the material 20 ride on the lower portions of therollers whose services extend for example, 1/4 inch above the planes ofthe side walls 74, 84. The detailed structure of the series of verticalaxis rollers 100, 110, 120 and 100a, 110a, 120a will be discussed ingreater detail in connection with FIGS. 5, 6 and 7.

With further reference to FIGS. 2 and 3 and also with reference to FIG.4 which is front end view in cross section of the strip mill entryguide, it is preferable that both the right edge guide 70 and the leftedge guide 80 be lined with abrasion-resistant material such as type4340 Alloy Steel Liners hardened to approximately 45 R_(c) so as tominimize wear of the guides 70, 80 caused by engagement with the edgesof the strip material during threading operations as discussed earlier.The liners for the guides are machined with rounded and tapered edgeswhere possible so as to not catch on the material 20 moving throughthem. With reference to FIGS. 2, 3 and 4, the top plate 72 has fastenedto its lower side, an abrasion-resistant guide 72a. In a similar manner,the side wall 74 is provided with an abrasion-resistant lining 74a whilethe lower plate 76 of the guide 70 is provided on its upper surface withan abrasion-resistant lining 76b. In a similar manner, guide 80 includesabrasion-resistant linings 82a, 84a and 86b.

The guides 70, 80 are movable toward and away from each other toaccommodate different widths of the material. Such movement toward andaway from each other is provided by a screw mechanism that will now bediscussed.

The guide 70 is supported upon a front carriage 90 and a rear carriage94. The carriages 90, 94 in turn are supported on and ride back andforth upon, respectively, a front carriage support rail or way 92 and arear carriage support rail or way 96. In a similar manner, the guide 80is supported upon its associated front carriage 90a and rear carriage94a both of which ride on the ways 92, 96. With specific reference toFIG. 2, way 92 is of generally triangular shape so as to accommodateboth vertical and horizontal forces put on it by the carriage 90. Theway 92 is supported by a frame cross member 32c as illustrated. Thecarriage 90 includes a pair of bearing pads 90b, 90c that ride on theupper surface of the way 92. As also shown in FIG. 2, the rear carriagesupport rail or way 96 is of a generally inverted channel shape andprovides a top surface upon which a bearing pad element 94b rides. Theends of the way 96 are fixed and mounted to the frame 32. Thus, thecarriages 90, 94 and 90a and 94a ride on the ways 92, 96 and move towardeach other or away from each other depending upon the width of the stripmaterial 20 being worked.

With specific reference to FIGS. 2 and 4, the noted movement of theguides 70, 80 toward and away from each other is effected by means of apair of rotating screw drives 98, 99. The screw drive 98 is locatedwithin the way 96, while the screw drive 99 is positioned toward thefront or feed end of the guide 30 is located adjacent to the way 92, asillustrated. With specific reference to FIG. 4, the screw drive 99 isillustrated in greater detail, it being recognized that the drive 98 isof generally similar construction and function. As shown in FIG. 4, thescrew drive 99 extends transversely across the extent of the guide 30and is rotatably supported at its middle and at both ends by suitablebearing structures, which are, in turn, supported by the frame of theguide. The screw drive 99 threadingly engages a right edge guidefollower 99a fixed to the guide 70 as illustrated, while a left edgeguide follower 99d is fixed to the left guide 80. The front screw drive99 is provided at its left end portion as viewed in FIG. 4, with aleft-hand thread segment 99c while its right-hand portion is providedwith a right-hand threaded portion 99b. Upon rotation of the shaft end99f of the screw drive 99 due to the counterthreaded portions 99c, 99b,the followers 99a, 99d will move either toward each other or away fromeach other. Rotation of the screw actuator 99 by means of the shaft 99fis accomplished by a suitable electric motor (not shown) mounted to andsupported by a separate frame (not shown). To keep dirt and debris frominterfering with operation of the screw actuator 99, a suitable cover99e is provided that can expand and collapse in length in a manner knownin the art. As shown in FIG. 2, the screw actuator 98 is drivinglyconnected to the actuator 99 via an appropriate gear drive train 97schematically illustrated. Thus, rotation of the shaft 98 and 99 occurssimultaneously because of the their interconnection via the gear train97. The screw actuator 98 is similar in design to the earlier discussedactuator 99 illustrated in FIG. 4 but is contained within the way 96, asillustrated, so as to be protected from dirt and debris. As shown inFIG. 3, the carriages 94, 94a include at their lower, under endsfollower portions that respectively ride on counterthreaded halves ofthe screw actuator 98 in a manner similar to followers 99a, 99d (seeFIG. 4) discussed earlier.

Thus, it can be seen that by appropriate movement of the screw drives98, 99 the guides 70, 80 move toward and away from each other. Also, asshown in FIG. 4 and as discussed earlier with regard to FIG. 2,operation of the hydraulic actuator 34 causes overall movement of theguide 30 toward and away from the mill rollers 12a, 12b, the guide 30having its lowermost end 19c riding upon tracks or ways 19a, 19b fixedin position relative to the mill floor 19, as shown in FIG. 4.

As earlier mentioned, and with specific reference to FIGS. 1 and 3, themovement of the guide 30 towards the mill rollers 12a, 12b is limited bythe stop mechanisms 50. The stop mechanisms 50 include a wheel 52, ascrew 54 and a stop 56 whereby manual rotation of the wheel 52 causesthe screw 54 to advance or retract, adjusting the position of the stop56. The stop 56 engages the frame 12c of the mill 12 to limit thecloseness of the guide 30 to the mill rollers 12a, 12b (see FIG. 1).Therefore, by calibration of the stop mechanism, the precise distancebetween the guide 30 and the mill rollers 12a, 12b can be established,maintained and readily adjusted.

With further reference to FIGS. 2 and 4, the right or feed end of theguide 30 provides a relatively wide throat for initially receiving theleading edge of the material 20 as it is being fed into the nip 12d.Once the material has been threaded through and between the guides 70,80 it can be supported at its outer edges by the bottom plates 76, 86and at its middle by a center guide rail 130 having at its upper end anabrasion-resistant surface 130a of a material identical or similar tothe earlier discussed abrasion-resistant material lining the guides 70,80. It should be noted that during steady state operation, the material20 is actually slightly spaced above the bottom plates 76, 86 and thecenter guide rail 130 wherein only the outer vertical edges of thematerial 20 engages the lower portions of the series of rollers 100,110, 120 and 100a, 110a, 120a.

While vertical movement of the leading edge of the strip material 20 iscontrolled and guided by the upper and lower plates 72, 76 and 82, 86 ofthe guides 70, 80, horizontal or sideways movement is controlled andguided primarily by the series of rollers along the side walls 74, 84 ofthe guides. With specific reference to FIG. 3, it can be seen that thefeed or front end of the guide 30 provides a throat for receiving theleading edge of the material 20 wherein the front end of the side walls74, 84 are flared outwardly away from each other. It can also be seenthat the rollers 120, 120a are of a diameter approximately twice thediameter of the downstream rollers 110, 110a and 100 and 100a. Inaccordance with the invention, the larger diameter rollers 120, 120a atthe front or upstream end of the guide 30 are designed to accommodatehigher impact forces experienced by these rollers, since they are oftenthe first rollers to engage and forcibly guide the leading edge of thestrip material. The rollers 120, 120a are the primary means for engagingand forcing the leading edge of the strip 20 into an alignment with theremaining rollers 100, 100a and 110, 110a. As noted earlier, during asteady state operation, only the side edges 20a, 20b of the material 20are in contact with the series of rollers along the guides 70, 80 so asto minimize abrasion of the guides and also reduce frictional wear ofthe material 20 as it is worked.

As noted earlier, the material 20 is at high temperature when it isworked. To avoid overheating of the lower ends of the rollers engagingthe side edges of the material, and thus degradation of the rollers, aplurality of spray nozzles 140 are provided, each being adjacent to alower portion of the rollers (see FIGS. 3 and 4). A water-based coolingliquid is sprayed on the lower portions of the rollers during operationto reduce their temperature thereby minimizing roller surfacedegradation.

In accordance with the present invention, when the lower portions of therollers 100-100a, 110-110a, 120-120a are worn to a predetermined degree,the rollers can be easily inverted whereupon the less-worn upperportions now primarily engage the edges of the material 20 so as topermit continued operation of the machine. The structure and mounting ofthe rollers facilitating such roller inversion will now be more clearlyillustrated with regard to FIGS. 5, 6, and 7.

As shown in FIG. 5, roller 120 is of the largest diameter and as notedearlier, is farthest from the nip into which the material is being fed.The roller 120 is also of greatest length wherein the lengths of rollers110, 100 decrease. This variation in length accommodates the decreasingvertical movement or oscillation of the leading edge of the material asit progresses from roller 120 then past roller 110 and finally pastroller 100 before entering the nip. Also as shown in FIG. 5, line 20cillustrates the pass line of the strip material 20 when in a steadystate operation of the guide and mill. Thus, for the most part, it isonly the lower portions of the rollers that regularly engage the stripmaterial 20. With specific reference to FIGS. 6 and 7, roller 120 isillustrated, it being recognized that the remaining rollers are ofgenerally identical construction but for their dimensions. The roller120 includes an outer cylindrical shell 150 of high strength material soas to provide for a relatively thin wall thickness. Thus, an elementwith low weight and low inertia is provided whereby the initialengagement of the edge of the material 20 with the outer surface of theshell 150 will cause the shell to rotate quickly, as opposed to the casewhere the shell 150 is of higher mass. Therefore, in accordance with thepresent invention, the weight of the shell 150 is minimized to theextent possible, preventing low inertia forces to the incoming sheetmaterial and allowing the roller to accelerate to a given speed in aminimum amount of time, thus minimizing abrasion between the roller andthe edge of the material as the roller comes up to speed upon engagementwith the material.

The shell 150 is rotatably supported by a spindle member 152 thatextends through the center of the shell 150 as shown. The spindle 152 isfixed in position and carries at its upper and lower ends appropriateroller bearings. More specifically, such bearings includes outer races154, 154a, roller members 156, 156a and inner race members 158, 158a, asillustrated. Such bearing assemblies are commonly referred to as taperedroller bearing assemblies and their operation and structure is wellknown in the art. The outer surfaces of the outer races 154, 154a engageand are received into the ends of the shell 150 while the inner races158, 158a fit over and engage the ends of the spindle 152. An upperroller cap 160 and a lower roller cap 160a capture the shell 150, thespindle 152 and the associated bearing assemblies between them. Whilethe lower cap 160a is supported by the lower plate 76 of the guide, theupper cap 160 is held down in its position by an end plate 165 which inturn is fastened to a portion of the upper guide plate 72 by appropriatebolts 167, 168 as shown. The spindle 152 includes a network oflongitudinal and transverse ports 152a through which lubricant isforced, the lubricant being diverted toward the upper and lower bearingassemblies by appropriate seal members 152b, 152c. Thus, pressurizedlubricant continuously flows to a limited degree through the bearingassemblies to ensure proper lubrication at all times. Thus, the seriesof rollers along the guides 70, 80 as discussed earlier are constantlylubricated to ensure smooth operation and minimal bearing wear whilealso being cooled at their lower ends by the water-based spray nozzlenetwork.

From the foregoing, it can be seen that an entry guide for a strip millhas been provided which is of simple yet rugged construction and whichwill provide accurate guiding of strip material into a set of millrollers with minimal wear on both the guide and the strip material thatit is handling due to the configuration and design of the guidesincluding the associated series of rollers extending along such guides.Due to constant lubrication and cooling of the rollers, extendedoperation of the guide is possible so as to minimize downtime. Also,when the lower ends of the guide rollers have worn to a predetermineddegree, the rollers can be easily inverted so as to provide the lesserworn upper surfaces for engagement with the edges of the material beingrolled. When the former upper ends of the rollers are worn, the rollerscan be disassembled and whereupon their outer shell portions can bereplaced quickly and easily, thereby returning the guide mechanism toservice.

It should be evident that this disclosure is by way of example and thatvarious changes may be made by

adding, modifying or eliminating details without departing from the fairscope of the teaching contained in this disclosure. The invention istherefore not limited to particular details of the disclosure, except tothe extent that the following are necessarily so limited.

What is claimed is:
 1. A mechanism for feeding strip material into a nipbetween a pair of strip mill rollers, said strip material being anelongated horizontally extending strip of indeterminate length, saidstrip having horizontal top and bottom surfaces, and vertical sideedges, said mechanism comprising:a frame structure movable toward andaway from said rollers; a pair of opposed horizontally extending guidesmounted on said frame for engaging and capturing the vertical side edgesof the strip material, said guides defining a horizontally extendingchannel that vertically tapers as said strip material moves through saidchannel toward said nip; and a series of vertical axis rollers mountedon and extending along a horizontal length of each guide, each verticalaxis roller having an upper portion and a lower portion, the side edgesof the material sequentially engaging and riding on primarily said lowerportions of said vertical axis rollers as the material moves toward thenip, each vertical axis roller being of a vertical length substantiallygreater than an expected thickness of the strip material wherein, due tosaid engagement of said side edges primarily with the lower portions ofthe vertical axis rollers, said lower portions wear faster than saidupper portions, said vertical axis rollers being invertible to allowwear of said upper portions subsequent to said wear of said lowerportions.
 2. A mechanism according to claim 1 wherein each of thevertical axis rollers have a length and are spaced a distance from thenip, the length of said rollers decreasing as their distance from saidnip decreases.
 3. A mechanism according to claim 1 wherein each of thevertical axis rollers have a diameter, the diameter of the vertical axisrollers farthest from the nip being greater than the diameter of thevertical axis rollers closest to the nip.
 4. A mechanism according toclaim 1 including means mounted on said frame for spraying coolingliquid on only said bottom portions of said vertical rollers.
 5. Amechanism according to claim 1 including at least one manuallyadjustable stop mounted on said frame and engageable with a frameportion of said strip mill rollers to limit movement of said mechanismtoward said strip mill rollers.
 6. A mechanism for feeding stripmaterial into a nip between a pair of strip mill rollers, said stripmaterial being an elongated horizontally extending strip ofindeterminate length, said strip having horizontal top and bottomsurfaces, and vertical side edges, said mechanism comprising:a framestructure movable toward and away from said rollers; a pair of opposedhorizontally extending guides mounted on said frame and simultaneouslymovable toward and away from each other to accommodate different widthsof said strip material, said guides engaging and capturing the verticalside edges of the strip material, said guides each including a topplate, a bottom plate, and a sidewall, said plates and sidewallsdefining a horizontally extending channel that vertically tapers as saidstrip material moves through said channel toward said nip, a distancebetween said top and bottom plates increasing as said top and bottomplates extend away from said nip; and a series of vertical axis rollersmounted on said guide and extending along a horizontal length of eachsidewall, each vertical axis roller having an upper portion and a lowerportion, the side edges of the material sequentially engaging and ridingon primarily said lower portions of said vertical axis rollers as thestrip material moves toward the nip, each vertical axis roller being ofa vertical length substantially greater than an expected thickness ofthe strip material wherein, due to said engagement of said side edgesprimarily with the lower portions of the vertical axis rollers, saidlower portions wear faster than said upper portions, said vertical axisrollers being invertible to allow wear of said upper portions subsequentto said wear of said lower portions.
 7. A mechanism according to claim 6wherein said sidewalls include first and second ends, said first endsbeing closest to said nip and said second ends being farthest from saidnip, said sidewalls tapering away from each other at the ends farthestfrom said nip.
 8. A mechanism according to claim 6 wherein said verticalaxis rollers along said guides are of different lengths and diametersand are spaced different distances from said nip, vertical axis rollersspaced farthest from said nip having a diameter and length greater thanvertical axis rollers closer to the nip.